[Cen-Tejas]

..........just saw this this Sunday morning!

What my tech guy told me to do is just “turn it off” and it will go away. In my case, this threat was precisely known to him and all IT guys/gals. Namely, the culprits put a window saying EMERGENCY...........call Microsoft. Well, I bit and called the number. They sounded totally legit and even with background noise etc etc. But they were not Microsoft. They were crooks.

[palmer]

The EMERGENCY: CALL MS window is completely fake, put up by a rogue website usually using Flash. That venerable scam has zero relation to the port 139 attack, although they may claim otherwise. Usually they want you to call so they can "fix" your computer remotely. If you turn on remote desktop for them, you are pretty much cooked. If you do not, and do not do anything else they recommend, then you are safe.

They will claim otherwise and give you "proof" that you have been hacked which is all lies. I have salvage computers that they were let into via someone turning on remote desktop. But it's not easy or pretty (I often end up with broken drivers as I try to remove various infections).